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Forest Management In A Changing Climate: Integrating Social And Biopysical Sciences To Inform Adaptive Responses To Future Uncertainty, Peter Breigenzer Dec 2023

Forest Management In A Changing Climate: Integrating Social And Biopysical Sciences To Inform Adaptive Responses To Future Uncertainty, Peter Breigenzer

Electronic Theses and Dissertations

Forests provide numerous ecological and socio-economic benefits, yet climate change is creating novel and extreme conditions that threaten forests and disrupt traditional management practices. To address future uncertainty about how to manage forests amid a rapidly changing climate, researchers have developed adaptive management strategies that move away from using historical ecological baselines as management goals. However, despite increases in adaptive forest management frameworks, there are still concerns that private woodland owners (PWOs; also known as family forest owners or non-industrial private landowners) are not adopting beneficial practices. Additionally, since tree canopies often buffer understory microclimates (i.e., fine scale variation in …


A Bi-Hemispheric Perspective On The Last Glacial Maximum And Termination Using 10be Surface-Exposure Chronologies From An Interhemispheric Asia-Zealandia Transect, Peter Strand Aug 2023

A Bi-Hemispheric Perspective On The Last Glacial Maximum And Termination Using 10be Surface-Exposure Chronologies From An Interhemispheric Asia-Zealandia Transect, Peter Strand

Electronic Theses and Dissertations

Late-Pleistocene glacial cycles represent the largest natural changes to Earth’s climate over the past one million years, and yet determining the underlying drivers remains a major mystery in paleoclimate. The observation of generally synchronous glaciation and deglaciation between the polar hemispheres (Mercer, 1984) runs contrary to long-standing ice age theory (e.g. Milankovitch, 1941), and was recently dubbed ‘Mercer’s Paradox’ (Denton et al., 2021). In this thesis I derive regional climate records from mountain glaciers along an interhemispheric Australasian transect, extending from the Mongolian Altai to the Southern Alps of New Zealand, to test the existence of Mercer’s Paradox in the …


Influence Of Biochar As A Soil Amendment On Soil Water Content And Wild Blueberry Physiology, Abigayl Novak May 2023

Influence Of Biochar As A Soil Amendment On Soil Water Content And Wild Blueberry Physiology, Abigayl Novak

Electronic Theses and Dissertations

Maine wild (or lowbush) blueberries (Vaccinium angustifolium Ait.) continue to face challenges imposed by climate change. Reduced frequency of precipitation and increased drought conditions have negatively impacted this crop since it resides in sandy soils with limited retention of water and nutrients. The wild blueberry plants growing in water- and nutrient-poor sandy soils are likely to have poor resilience to drought, resulting in a decline in berry yield during drought years. Thus, there is an urgent need to find a drought management solution for wild blueberries. Compared with other drought management practices, such as irrigation systems, mulching, and adopting drought-resistant …


Climate Change And An Evolving Fishery: Do Declining Maternal Size And Planktonic Foods Affect Lobster Larval Survival In The Gulf Of Maine?, Alexander J. Ascher May 2023

Climate Change And An Evolving Fishery: Do Declining Maternal Size And Planktonic Foods Affect Lobster Larval Survival In The Gulf Of Maine?, Alexander J. Ascher

Electronic Theses and Dissertations

Many marine organisms exhibit bipartite life-cycles whereby reproductive adults dwell on the benthos while the larvae are pelagic. The pelagic stage is subject to mortality rates which far exceed those experienced by the organism during its benthic existence. The larval phase therefore represents an important bottleneck to larval recruitment. Small changes to survivorship in the plankton can have large consequences for subsequent year-class strength. Understanding the factors influencing successful larval recruitment is an important step towards predicting future stock abundances and maintaining healthy fisheries. The American lobster (Homarus americanus) is a large benthic crustacean which is economically and culturally important …


A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell Dec 2022

A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell

Electronic Theses and Dissertations

Alpine ecosystems around the globe are at risk due to climate change, human disturbance, and habitat loss. New England alpine zones are small and fragmented, which could make them vulnerable to global change. However, the persistence of tundra relics throughout the Holocene suggests the persistence of these communities in microclimate refugia. Assessing the near-term vulnerability of alpine plant communities is challenged by a lack of standardized, repeat surveys and long-term monitoring data, which presents a challenge for the many agencies monitoring New England’s alpine zones. Island biogeography theory predicts that alpine species richness is a function of area, but this …


Modeling Life History And Population Dynamics Of American Lobster And Atlantic Sea Scallops In A Warming Gulf Of Maine, Cameron T. Hodgdon Aug 2022

Modeling Life History And Population Dynamics Of American Lobster And Atlantic Sea Scallops In A Warming Gulf Of Maine, Cameron T. Hodgdon

Electronic Theses and Dissertations

Climate change is impacting many marine species distributions, life histories, and behaviors, as well as their associated fisheries and overall production. This is perhaps especially true for the Gulf of Maine (GOM). Here, warming rates are exceeding a vast majority of the world’s oceans. This highly dynamic system supports myriad species, but is both economically recognized and culturally known for its Atlantic sea scallop (Placopecten magellanicus) and American lobster (Homarus americanus) fisheries. This dissertation examines the influence of regional climate change on these species in an effort to predict how these stocks and their fisheries may …


Assessment Of Historical Climate Variability In Maine With Implications For Future Agricultural Productivity And Adaptation, Carly Frank Aug 2022

Assessment Of Historical Climate Variability In Maine With Implications For Future Agricultural Productivity And Adaptation, Carly Frank

Electronic Theses and Dissertations

Climate change is a wicked problem with global impacts, one of which being the sustainability of the existing global food system. As temperatures and variability in precipitation are projected to increase, the challenges to agriculture are expected to intensify. This thesis examines the Maine historical climate record over the growing season, in combination with future projections, to assess how conditions have changed and will change with agricultural implications. In this analysis, relevant climatic variables are analyzed, and agriculture-significant measures are derived for Maine’s three climate divisions using four decades of daily and monthly gridded datasets. In addition, this thesis explores …


Anthropogenic Impacts To Essential Habitats In The Gulf Of Maine: A Case Study Of The American Lobster, Homarus Americanus, And Its Fishery, Andrew Goode Dec 2021

Anthropogenic Impacts To Essential Habitats In The Gulf Of Maine: A Case Study Of The American Lobster, Homarus Americanus, And Its Fishery, Andrew Goode

Electronic Theses and Dissertations

The Gulf of Maine has been fundamentally altered by anthropogenic forcings for decades and offers an ideal study system to monitor response to change. Through complex interactions between ocean warming, altered demographic bottlenecks, and reduced top-down controls, the American lobster (Homarus americanus Milne Edwards) capitalized on favorable conditions and proliferated within the Gulf of Maine. These changes catalyzed the expansion of the lobster fishery, elevated its status as North America’s most valuable marine resource, and shifted coastal communities towards a virtual lobster monoculture. The same processes that facilitated lobster to capitalize on favorable conditions may come with unintended consequences …


Adaptation Strategies For Wild Blueberry Growers In A Changing Climate: Mulching Effects On Crop Productivity And Fertility Effects On Blueberry Gall Midge, Rebecca Gumbrewicz Dec 2021

Adaptation Strategies For Wild Blueberry Growers In A Changing Climate: Mulching Effects On Crop Productivity And Fertility Effects On Blueberry Gall Midge, Rebecca Gumbrewicz

Electronic Theses and Dissertations

Wild blueberry (Vaccinium angustifolium Aiton.) cropping systems are considered resilient to environmental changes due to ecological and genetic diversity within each field. However, wild blueberries can be sensitive to weather fluctuations that cause extreme temperature or moisture regimes. Climate change in Maine is represented by increasing rates of warming temperatures, more intense precipitation events, and more frequent atmospheric “blocking” patterns. Warming temperatures result in the northward expansion of pest ranges and altered growing seasons. More extreme rainfall events lead to damaged plantings and soil erosion. Atmospheric blocking leads to an increased likelihood of heat waves and drought. Two experiments were …


A Social-Ecological Examination Of Moose In Maine: Habitat, Management, And Changing Seasonality, Asha Dimatteo-Lepape Aug 2021

A Social-Ecological Examination Of Moose In Maine: Habitat, Management, And Changing Seasonality, Asha Dimatteo-Lepape

Electronic Theses and Dissertations

Maine is a New England state with rich ecosystems and diverse opportunities for enjoying the outdoors. Maine is well known as a popular nature-based tourist destination, and is often associated with its notable moose population. Social-ecological systems in Maine are highly intertwined, and as such, are especially susceptible to impacts resulting from climate change. Moose health in the state is already being negatively impacted by climate change with high infestation rates of winter tick resulting in declining moose health and high moose calf mortality. Given that late winter is a time of high stress and increased mortality of moose due …


Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen Aug 2021

Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen

Electronic Theses and Dissertations

Climate change is expected to lead to novel drought conditions in the Northeastern United States. Therefore, experimental studies that mimic these conditions are crucial to understand the potential impact on forests. Further, recent large scale dendrochronological studies suggest that spring and summer droughts may immediately impact tree growth while fall droughts may cause delayed impacts on growth the following growing season. Therefore, in this study, we investigated the impacts of six-week-long spring, summer, and fall droughts on the physiology and intra-annual growth on 288 saplings of six tree species native to the Northeastern United States. These species (deciduous broadleaf angiosperms, …


The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang Aug 2021

The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang

Electronic Theses and Dissertations

The Gulf of Maine northern shrimp (Pandalus borealis) once supported a significant winter fishery for the Gulf of Maine (GOM). Although the shrimp fishery is not comparable to the lobster business, it provided fishermen and many coastal communities jobs and incomes in winters after lobster seasons. However, a moratorium has been put on the shrimp fishery since 2014 due to record low population abundance and perceived recruitment failures. The recruitment failures have been correlated with warming water temperatures over the past decade. The GOM has been recognized as experiencing rapid warming as a result of global climate change. …


The Future Of Maine's Forests Under Alternative Socioeconomic, Climate And Conservation Pathways, Jianheng Zhao Dec 2020

The Future Of Maine's Forests Under Alternative Socioeconomic, Climate And Conservation Pathways, Jianheng Zhao

Electronic Theses and Dissertations

Maine is a historically important timber supply region in North America and understanding the potential change in forestlands and their product industries affected by climate change and various socio-economic conditions can better improve the forest healthy and sustain a sustainable product industry. A statistical harvest choice model for the state of Maine was developed in chapter 1. It was estimated using a multinomial logit model of two products, under varying management intensities, and ownership classifications across varying market conditions. Results indicate that stumpage prices have a significant effect on forest landowners' harvest decisions and that the expansion of conservation land …


Fostering Coastal Destination Resilience In Maine: Understanding Climate Change Risks And Behaviors, Lydia Horne Dec 2020

Fostering Coastal Destination Resilience In Maine: Understanding Climate Change Risks And Behaviors, Lydia Horne

Electronic Theses and Dissertations

Tourism is an increasingly important global industry. Coastal and nature-based tourism destinations are especially vulnerable to climate change. Trends in visitation are expected to shift under changing climate conditions, influencing tourist travel behaviors related to destination selection, timing of visits, and activity participation. Tourism suppliers’ adaptation and mitigation behaviors have the potential to alleviate negative shifts in visitation and respond to negative climate change impacts, while also enabling suppliers to take advantage of emerging opportunities. The purpose of this dissertation is to understand how tourism stakeholders, including tourism suppliers (i.e., business owners, managers) and consumers (i.e., visitors), perceive their risk …


Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina Nov 2019

Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina

Electronic Theses and Dissertations

Lake Auburn, Maine, USA, is a historically unproductive lake that has experienced multiple algal blooms since 2011. The lake is the water supply source for a population of ~60,000. We modeled past temperature, and concentrations of dissolved oxygen (DO) and phosphorus (P) in Lake Auburn by considering the watershed and internal contributions of P as well as atmospheric factors, and predicted the change in lake water quality in response to future climate and land-use changes. A stream hydrology and P-loading model (SimplyP) was used to generate input from two major tributaries into a lake model (MyLake) to simulate physical mixing, …


Assessing The Mechanisms And Implications Of Altered Carbon Cycling In Arctic And Boreal Lakes, Rachel Fowler May 2019

Assessing The Mechanisms And Implications Of Altered Carbon Cycling In Arctic And Boreal Lakes, Rachel Fowler

Electronic Theses and Dissertations

Dissolved organic carbon (DOC) is an important component of lake ecology, as it contributes to light attenuation and carbon cycling. In recent years, DOC declined in a suite of lakes in Greenland. I performed experiments to test potential mechanisms of DOC loss. The tested mechanisms did not reduce DOC concentration, but DOC composition was affected. I also paired water quality data with meteorological observations to evaluate effects of climate drivers on lake variables. The lake variables were temporally coherent and associated with patterns of mean annual precipitation.

In the northeastern U.S., recovery from acidification and climate change have contributed to …


Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias May 2019

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …


Living On The Edge: Thermophysiology Of The Southern Flying Squirrel At Its Northern Range Margin, Vanessa R. Hensley May 2019

Living On The Edge: Thermophysiology Of The Southern Flying Squirrel At Its Northern Range Margin, Vanessa R. Hensley

Electronic Theses and Dissertations

Climate change has the potential to upset entire ecological systems, making predictive models of the utmost importance. The incorporation of physiological parameters into predictive models not only bolsters their accuracy but also provides a mechanistic explanation for ecological changes already observed and those yet to come. North American flying squirrels, for example, have already experienced dramatic range shifts northward over recent decades, with climate change being the suspected driver. While other studies have focused on warming winter temperatures, I explored the hypothesis that rising summer temperatures were driving the observed range shifts. Unable to find a reliable population of the …


Ecological And Economic Implications Of Increased Storm Frequency And Severity For Boreal Lakes, Kathryn Warner May 2019

Ecological And Economic Implications Of Increased Storm Frequency And Severity For Boreal Lakes, Kathryn Warner

Electronic Theses and Dissertations

In boreal regions, increased precipitation events have been linked to increased concentrations of dissolved organic carbon (DOC), however less is known about the extent and implications of these events on lakes. We assessed the effects of precipitation events on six drinking water lakes in Maine, USA to better understand how DOC concentration and quality change in response to precipitation events. Our results revealed three types of responses: (1) an initial spike in DOC concentrations and quality metrics; (2) a sustained increase in DOC concentrations and quality metrics and; (3) no change during all sampling periods. Lake residence time was a …


Modern And Paleoecological Perspectives On A Terrestrial-Marine Linkage In The Falkland Islands, Dulcinea V. Groff Oct 2018

Modern And Paleoecological Perspectives On A Terrestrial-Marine Linkage In The Falkland Islands, Dulcinea V. Groff

Electronic Theses and Dissertations

The Falkland Islands are a biodiversity hotspot in the South Atlantic Ocean, with some of the world’s most important populations of seabirds and seals. The impact of climate change on these marine populations and their coastal breeding habitat in the Falklands is unknown. Coastal grasslands of Poa flabellata (tussac grass) form critical breeding habitat for wildlife, but have been heavily degraded by the introduction of livestock in the 17th century. This dissertation investigates the impacts of global change (climate change, grazing) on P. flabellata and its sensitivity to the fecal nutrient subsidies provided by marine wildlife. Chapter 1 provides …


Developing A Risk Assessment Protocol To Quantify Distribution And Uptake Of Persistent Organic Pollutants In Glacial Outflows, Kimberley Rain Miner May 2018

Developing A Risk Assessment Protocol To Quantify Distribution And Uptake Of Persistent Organic Pollutants In Glacial Outflows, Kimberley Rain Miner

Electronic Theses and Dissertations

Pollutants released by industrialized nations between 1960 and 2004 have been transported northward through atmospheric processes and deposited into glaciated alpine ecosystems. Many of these chemicals retain their original structure and are absorbed into the biota thousands of miles away from where they were originally utilized. With a warming climate increasing the melt of alpine glaciers, these glaciers may be introducing growing amounts of toxins into the watershed. While studies have demonstrated the existence of resident pollutants within glaciated ecosystems, no one has developed a risk assessment to identify sources and quantity of risk posed by these compounds when released …


Marine Protected Areas In Areas Beyond National Jurisdiction: Defining "Success" For Conservation And Management, Emily Suzanne Nocito May 2018

Marine Protected Areas In Areas Beyond National Jurisdiction: Defining "Success" For Conservation And Management, Emily Suzanne Nocito

Electronic Theses and Dissertations

With growing attention to and use of marine protected areas [MPAs], there are an increasing number of policy goals ascribed to these area-based management tools [ABMT]. One expectation is that an MPA can increase system “resilience”, yet oftentimes resilience – including whether we are considering social, economic or ecological resilience – stays unspecified. In recent years, there has also been a specific focus on MPAs as tools to promote climate change resilient ocean systems. Through a meta-analysis of the scientific literature and an analysis of over one thousand three hundred voluntary commitments made at the United Nation Ocean Conference, this …


Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller Nov 2016

Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller

Electronic Theses and Dissertations

Anthropogenic warming and ocean acidification are occurring as CO2 continues to accumulate in the atmosphere (OA). Few studies have evaluated the joint effects of elevated temperature and partial pressure of CO2 (pCO2)on marine organisms. In this study we investigated the interactive effects of Intergovernmental Panel on Climate Change (IPCC) predicted temperature and pCO2 for the end of the 21st century on key aspects of larval development of the American lobster, Homarus americanus, an otherwise well-studied, iconic, and commercially prominent species in the northeastern United States and Atlantic Canada. Our experiments showed …


Role Of Dignity In Rural Natural Resource Governance, Tora Johnson Dec 2015

Role Of Dignity In Rural Natural Resource Governance, Tora Johnson

Electronic Theses and Dissertations

Dignity is “an internal state of peace that comes with the recognition and acceptance of the value and vulnerability of all living things” (Hicks, 2011, p. 1). Dignity is a crucial element in effective governance arrangements. This study applies dignity theory, and related theories of natural resource governance and environmental communication, to understand and overcome barriers to effective governance of common pool resources in rural communities. Chapter 1 reviews relevant literature on natural resource governance and develops a theoretical framework for dignity. Chapter 2 applies dignity theory to a contentious comprehensive planning process in a small Maine town in order …


Temperature Conditions At Orono, Maine, Ernest Claude Drew Jun 1912

Temperature Conditions At Orono, Maine, Ernest Claude Drew

Electronic Theses and Dissertations

This thesis is an outgrowth of a much larger piece of work which the Department of Physics, thru its instructors and major students, has undertaken to complete. The task referred to, is the compilation, arrangement, and summarizing of the various meteorological records taken at the University of Maine for the past forty-four years. These records were begun in the above department by Dr. M. C. Fernald in the year 1869 and were continued by him until 1893. The work was then transferred to the Experiment Station, where observations were made under the direction of Doctors W. H. Jordan and C. …